When I connect the monitor I get "VGA no signal" and the monitor screen stays blank.

I have selected the monitor as the display device on the laptop. The information on the monitor displays the correct screen resolution from the laptop, so the monitor is communicating in some way with the laptop.

Maybe a bit late. When every thing fails (resolution, another monitor, drivers), try this. But, some TVs check if the signal is available using a communication protocol with the PC. And some PC doesn't connect VGA pin 10 (GND) to the connector chasis, so the TV can't talk with the PC and assumes that there isn't any signal. It must work if you short pin 10 to the connector chasis.

Most laptops have a function-key combination you must press to activate the external monitor. On ThinkPads it's FN-F7. I don't know what it is on the Asus--look for a keycap that has a little picture of a monitor, and press the Fn key and that.

You can also try powering off the laptop, plugging in the monitor, and powering on. On some laptops a monitor is only detected if it's present at power-on.